Water-heater



M. H. COWAN.

' WATER HEATER. APPLICATION FILED FEB. 15, I919.

1,338,447. Patented Apr. 27, 1920.

3 SHEETS-SHEET 1.

INVENTOR 4 AT RNEY M. H. GOWAN.

WATER HEATER.

urucmou FILED m. as, 1919 Patented Apr.27,1920.

3 SHEETS-SHEET 2- III! III I 111111! INVENTORI JIamvwJfirfier? a w TTNEY MAURICE HERBERT OOWAN, 0F BROOKLYN, NEW YORK.

WATER-HEATER.

Specification of Letters Patent.

Patented Apr. 27, 1920.

Application filed February 15, 1919. Serial No. 277,138.

To (ZZZ whom it-mayeoncc'rn: I

Be it known that I, MAURICE HERBERT CoWAN, a citizen "of the UnitedStates, residing in the borough of Brooklyn, county of Kings,and Stateof New Yorlg have invented a certain new and useful lVa'ter- Heater,=ofwhich the following isa specification.

This invention is a water heater, intended for use of gas as a heatingmedium, and the device of the present invention is so constructed thatit-may be either associated with a gas range or may be usedindependently as a separate unit.

The 'objecto'f the present invention is to provide a heater of the typespecified which will "possess maximum efficiency for fuel consumption,and-this object is attained-through a novel disposition o'f'conduitpipes ortubes and the'manner-o'f applying heat thereto. The heater'ofthis invention is adapted to be associated with a hot water boiler orreservoir properly connected thereto 'insuch manner that the watercontained in the boiler fills the entire system. The water in the boileris heated to the desired temperature through the heating of the water inthe gpipes or tubes referred to, and, as the water :insaid-pipes isheated, it flows to the boiler after *well known principles ofthermo-siphon circulation.

Features of the invention other than those specified will "be apparent"from the hereinafter detailed description taken in conjunction with theaccompanying drawings.

ll n the accompanying drawings I have illustrated different practicalembodiments of the'inventiom but the constructions shown thereinarel tobe understood as illustrative only, and not as defining the limits ofthe invention.

Figure F1 is a perspective view of a well known type of lritchen gasrange with which is associated a heater embodying the present invention;

Fig. 2 is a perspective view showing a slightly modified form of heateradapted forvuse entirely independent of'a range or any other form ofheating or cooking means;

Fig. 3 is asez'tion in the plane of the line 33'of-Eig. 14:, showing thecoils within the heater in fullnelevation, the device as shown in Fig.-'3 being 'that form'of the invention illustrated in Fig. 11;

Fig. 4 is a section 'on the line -4-4-of Fig. 3;

Fig. '5 is a section on the line 55 'of Fig. '2;

Fig. 6 is a section on the line 6 6 of Fig. 5.

Figs. 7 and'8 are'detail views of differently shaped pipe coils whichmay beemployed in the carrying out of the present invention.

Referring to the drawings, and morepartlcularly, Figs. 1, 3, 4L. and 7,A designates an oblong cast iron'or sheet metal casing, preferably madeof such sizethat it'may b e readily mounted by meansof earsa on the endof any well known formof'gas range B, after the manner shown in Fig. 1.The casing A is preferably provided atoneside with a door a, throughwhich access may he had to the interior 0f the casing. The door may beof any size desired, but is-preferably made quite large to allow ofready acressto all partsof the interior ofthecasing, wherebythe same maybe cleansed "from time to time as occasion may require.

The top and sides of the casing are normally closed and the bottom isnormally sealed by means of a plate (has shown in Fig. 3. The topof thecasing is, however, preferably perforated as at-c,-to allow spent heatand gases free exit from'the interior of the casing, while the lateral"-wallof said casing is provided with a plurality of apertures 0"through which sufficient air "to properly support combustion may enter.

Positioned in the lower portion of the casing and preferablysupported onlugs ii, extending inwardly from the walls of plate C, is a gas burnerD, here shownin substantially the form of a double loop. Gas is fed inthe said burner from a main or head E, through two valve controlconnections e as shown best in Fig. 3, each connection feeding into oneof the looped portions of the burner. connected to one anotherinteriorly sothat each connection 6 feed both loops of the burner. Ifonly a relatively smallquantity of heat is desired, one of theconnections may be employed, but if maximum heat is wanted bothconnections may be opened. The gas flows fromthe burnerthrough theperforations d :formed therein :and :burns immediately exteriorlythereof.

Both portions of the burner are The introduction of heat into the casingin the manner described is for the purpose of heating Water to a desiredtemperature, and this water is subjected to the heating influence of theburner, by passing the liquid through a series of coils of a particularshape intendant to heat the water to the highest degree of efficiencyfor fuel consumption.

In the preferred embodiment of the invention, a relatively large body ofwater is maintained in a reservoir which may be a boiler F, of any ofthe well known and commonly used commercial forms. Leading from thelower end of the boiler to a series of coils interiorly of the casing Ais a feed pipe connectlon f, whne from the casing a return pipeconnection f leads the water back to the boiler. A closed circuit isthus provided through which the water circulates in accordance with wellknown hydrostatic principles due to the heating of the water in thecoils interiorly of the casing.

The heating coils which have been referred to as positioned interiorlyof the easing A form an important part of the present invention. It isof course well known that coils positioned within a casing and heated bygas flame have long been employed, but in every case the disposition ofthe coils were such that the efficiency of heating for fuel consumptionwas very low. This was due largely to the hit or miss practice ofdisplacement of the pipes or tubes within the heating chamber, and thisinefficient method of displacement, as well as the forming of the coils,necessitated the production of a large quantity of heat which escapedfrom the casing as waste fuel con sumption without having even beenbrought to impinge upon the tubes.

For example, in many of the well known forms of gas water heater, thecoils are in the form of a helix and are heated by a circular burnerpositioned immediately below and in the axis of the helix. In such construction, the major portion of the heat generated by the burner flowsunobstructedly up through the center of the helix and upwardly throughthe space between the helix and the casing, entirely free from contactwith the coils which it is supposed to heat. Accordingly, the heatwastage was large, only a relatively small portion of the fuel consumedfunctioning to heat the tubes. With the foregoing in mind, and afterprolonged experimentation, the coil displace-- ment illustrated in theaccompanying drawings was evolved, and, in practice, shows a bigincrease of efficiency over any of the constructions well known and nowemployed.

In accordance with this construction, the intake or feeder pipe fbranches interiorly of the casing A and immediately above the burner Dinto two or more tubes which are preferably copper or of some othersuitable material having a high conductivity coefficient. The two branchpipes h and h are formed to a large number of coils G and G of therespective tubes which extend upwardly to the top of the casing andconnect with the common outlet pipe f. These coils may differ slightlyin shape within'the limits of this invention, but the preferred form ofcoil employed is of the figure 8-shape as clearly shown in the drawings.The coils are preferably made of such size that they substantially fillthe cross sectional confines of the casing anda large numberof coils areformed in each tube. There is therefore what may be termed a pluralityof series of coils, the coils of each pipe forming one series entirelyindependent of the coils of the other pipe'which form the other series.The coils are, moreover, preferably so disposed that the coils of oneseries are alternately interspaced with those of the other series, sothat a very compact construction results in spite of the large quantityof tubing employed. The advantage of this construction is that the crosssectional area figuratively speaking, interlaced tubing so that the heatemanating from the burner D cannot pass unobstructedly upward past thecoils, but is forced to impinge said coils and perform the intendantfunction of heat.- ing the same. In practice, the heat circulatesupwardly between the coils heating each coil equally throughout. Thecoils are preferably subjected to the heat and the maximum of the burnerefliciency is secured.

In a slightly modified construction, illustrated in Figs. 2, 5 and 6,the casing A is provided with legs 6 so that the casing may stand byitself and independent of any other means of support. The casing ishowever preferably connected up in a pipe circuit with a boiler afterthe general method shown in Fig. 1 and the construction is in manyrespects, to the preferred embodiment hereinbefore described. However,as shown in Fig. 5, the burner D, although mounted in the lower portionof the casing is inclined so as to give it greater length and consequentgreater heating capacity. With this positioning of the burner, the coilsGr and G in order that they be made to substantially fill the chamber,above the burner, are graduated in size from the bottom to the top ofthe casing. The advantage of the construction shown in Fig. 5 is thatthe greater portion of the coils, from the bottom up, are subjecteddirectly to the action of the flame. However, both of the foregoingconstructions, the principle underlying in the present invention is thesame, since the coils are substantially coextensive with the crosssectional area of that portion of the casing above the burner wherebyheat arising from the burner is forced to impinge the coils, circulatebetween them and properly heat the same to a high degre of eificiency.

In Fig. 8 a modified form of coil is shown which may be employed, but,although this modified construction of coil will heat the water to afair degree of efficiency, due more particularly to other features ofthe invention, the form of coil shown in the remaining figures andspecifically in Fig. 7 is preferred, and as this latter form isconducive to the best results.

In gas heaters constructed in accordance with either of the foregoingembodiments of this invention, function in accordance with the same wellknown principles of the thermo-siphon system in the heating andcirculating of water through a closed circuit having therein a reservoirof the common kitchen boiler type. While the embodiment of the boilerand system is preferable to maintain a head or reservoir supply of waterin a heated condition, which may be drawn off, from time to time, ingreater or lesser quantities as desired, it is practical to use theheater to the exclusion of the boiler,

making a direct connection from the feed water pipe, through the heatingcoil and thence to a tap.

Having thus fully described the invention, what I claim as new, anddesire to secure by Letters Patent is:

A water heater embodying an upstanding casing, a gas burner extendingtransversely of the casing and inclined upwardly in a diagonal directioninteriorly of the casing, a water inlet and a Water outlet, one at thetop and one at the bottom of the casing, and a plurality of tubesconnecting said water inlet and outlet, said tubes being formed intosuperimposed alternately interposed figure-8 shapedloops ofprogressively greater dimensions from the lower portion of the casingupwardly to a point above the uppermost portion of the burner, while theremaining superimposed loops are of substantially the same dimensionsone to another, whereby maximum heat may be supplied to maximumradiating surface of the tubes in a relatively small and compact heater.

In testimony whereof I have signed my name to this specification.

MAURICE HERBERT COWAN.

